磷石膏作缓凝剂对油井水泥性能的影响

Influence of Phosphogypsum as Retarder on Performance of Oil-well Cement

利用工业废渣磷石膏替代天然石膏作油井水泥的缓凝剂,对不同熟料细度及不同磷石膏掺量对G级高抗油井水泥强度及抗硫酸盐侵蚀等性能的影响进行了研究。结果表明,水泥石强度随着油井水泥熟料细度的增加而增加,当油井水泥熟料的细度达到400m2/kg时,水泥石强度较高;随着磷石膏掺量的增加,水泥石强度呈现缓慢上升趋势,同时表明磷石膏替代天然石膏对水泥石强度影响不大,磷石膏替代天然石膏对高抗油井水泥的抗硫酸盐侵蚀性能未造成不良影响。

By using industrial scrap phosphogypsum instead of natural gypsum as retarder of oil-well cement, the influence of the dosage of phosphogypsum and the clinker fineness on the properties of the oil-well cement including compressive strength and sulphate resistance was studied in this paper. The results show that the compressive strength of cement block increases with the clinker fineness of the oil-well cement. When the fineness is above 400m2/kg, the strength of cement is relatively high. The compressive strength of cement block increases slowly with the content of phosphogypsum. Phosphogypsum instead of natural gypsum has little effect upon the compressive strength and the sulfate resistance properties of oil-well cement.